The technical scope of the invention is that of components allowing the ignition of a pyrotechnic composition or else of the propellant charge of a piece of ammunition.
Known igniters comprise a pyrotechnic composition able to generate a flame whose temperature is high enough to ignite a propellant charge or else a working pyrotechnic composition (smoke, flare or gas-generating composition for example).
The ignition composition is itself initiated by an electric means which can be a hot wire, an exploding wire or else a semi-conductor bridge.
These components suffer from drawbacks.
Thus, they all implement a pyrotechnic ignition composition, which has a certain sensitivity, notably to overheating or to electrostatic discharges.
The handling and manufacture of these components therefore presents certain risks and the ammunition or devices implementing such components also run the risk of inadvertent ignition.
Furthermore, known components only operate once and they therefore deliver all their energy further to the passage of a current through the electric ignition means. Such a mode of operation is abrupt and can cause ignition heterogeneities in the composition that are likely to disturb the future combustion rate and cause pressure waves.
It is therefore impossible using known components to spread the distribution of energy over time in order to control the ignition rate of the pyrotechnic composition or of the propellant charge.
It is known elsewhere, in the field of artillery, to use a plasma torch to generate pressure allowing a projectile to be fired.
These plasma torches can be used alone (see for example patent U.S. Pat. No. 2,899,864) or can be combined with a conventional solid or liquid propellant charge (see for example patent U.S. Pat. No. 5,231,242) in a gun commonly named the "Electro-Thermal-Chemical Gun".
Known plasma torches are of considerable size (around 200 to 300 mm long) and consume a lot of energy (around one Megajoule) released in a manner that is difficult to control.
When they are used alone, they are designed so as to supply pressure allowing the projectile to be fired.
When they are combined with a propellant charge, the pressure moving the projectile results both from the combustion of the propellant charge and the plasma pressure generated by the torch, plasma that also modifies the combustion rate of the propellant charge.
In any event, the pressure supplied by the torch is substantial enough to allow an increase in the velocity of the projectile whilst keeping up the level of pressure applied to it.
Using such torches to ignite a pyrotechnic composition is totally out of the question, the energy developed and the pressure generated risk disorganising or destroying the pyrotechnic composition.